Primary medulla oblongata teratomas.

Medulla oblongata teratomas are rare. The authors report 2 new cases of teratomas that occurred exclusively in the medulla oblongata. The first case was in a 9-year-old boy who presented with a 6-month history of neck pain and repeated paroxysmal vomiting. Based on preoperative radiographic findings, the initial diagnosis was of an intraaxial medulla oblongata hemangioblastoma. Intraoperatively, the cystic component of the tumor was gray, gelatinous, and soft in consistency. The solid component was light pink, rubbery, and nodular in appearance, with an identifiable boundary. The lesion was completely removed. Histopathological investigation revealed a mature teratoma. Postoperatively, the patient was supported with ventilator assistance and received a tracheotomy, but died of intracranial infection. The second case was in a 10-year-old boy with intermittent headache for 1 month. Radiographs revealed an exophytic cystic and solid lesion with dorsal involvement of the medulla oblongata. The lesion was predominantly solid, pinkish gray, tenacious, and moderately vascularized, with clearly delineated surgical dissection planes. The histopathological examination confirmed a diagnosis of immature teratoma. Total resection was achieved, followed by postoperative chemotherapy. He was alive without recurrence of the lesion or symptoms at 59 months after surgery. Resection of medulla oblongata teratoma is challenging, with inherent surgical risks that are contingent on the tumor growth pattern. Teratomas should be considered in the differential diagnosis of brainstem lesions. Chemotherapy has been suggested for immature teratomas. Long-term follow-up and larger studies of teratomas in unusual locations are required to improve practitioners' understanding of this disease's treatment and outcomes.